Alex Tsironis. COURTESY PHOTO Over the years, Alex Tsironis has been a coach, teacher and mentor to countless students throughout Montgomery County Public Schools.Tsironis, who was born in Silver Spring, currently heads up the Physical Education and Arts Department at North Bethesda Middle School.However, Tsironis, a Watkins Mill High School graduate, is perhaps best known as the creator of the popular MoCo Snow website and blog, at www.mocosnow.com, which began in 2010.“I loved snow days,” recalled Tsironis, “so I would always share my opinions with my kids.”